1. Field of the Invention
The present invention relates to an endoscopic suture apparatus that can be endoscopically inserted into a living body cavity and can suture or ligate organic tissues. More particularly, the invention relates to an endoscopic suture apparatus for performing suture to treat a damaged part of the tissue of the digestive canal or to reliably arrest hemorrhage in a bleeding region and to form an artificial valve in the treatment of a gastro-esophageal reflux disease.
2. Description of the Related Art
In general, tissues in the body of a patient are sutured in a surgical operation nowadays. Naturally, the patient's body cavity must be incised in the case of the surgical operation. The patient inevitably suffers a heavy invasion. Further, the patient must bear considerable costs including expenses of postoperative hospitalization that is required.
In view of this, it is desired that a medical treatment method be established, which uses a low-invasion oral endoscope and which obviates the necessity of incision of the patient's body.
The gastro-esophageal reflux disease (GERD) is one of diseases that affect more and more people these days. The principal symptoms of this disease include heartburn and mucosal break in the gullet. The disease is characterized in that it causes heavy pain to patients despite its benignancy. Hence, many patients require treatment. The main cause is a decrease in the function of the lower esophageal sphincter (LES) in the lower part of the gullet, which makes gastric acid flow upstream into the gullet.
A gastric-acid secretion inhibitor such as a proton-pump inhibitor is administered for treatment for the GERD. If the GERD is mild, its symptoms can be mitigated. A radical cure can be expected. However, a case wherein the function of the LES is lowered considerably and a serious case, such as a hiatal hernia, which involves an anatomical problem, can enjoy only a low effect of medication. These cases requires continuous administration, inevitably entailing high cost. Therefore, a surgical operation is applied to a serious GERD case. The Nissen fundoplication and Toupet methods are widely used as effective techniques.
In either method, the function of the LES is improved by wrapping the LES portion in the wall of the stomach, achieving a high curative effect. Recently, the laparoscopic technique has been established for treatment of lower invasion. However, there are numerous patients, and this disease is a benign disease, unlike cancer. There is a demand for the establishment of a method of treatment using a lower-invasion oral endoscope. To meet the demand, a method, or a technique, has been devised. In this method, a backward flow of gastric acid is prevented by using an artificial valve that is formed by ligating and bulging an organic tissue.
U.S. Pat. No. 5,792,153 (PCT National Publication No. 10-500318), Jpn. Pat. Appln. KOKOKU Publication No. 6-44,913, and Jpn. Pat. Appln. KOKAI Publication No. 11-313,826, for example, disclose endoscopic suture apparatuses.
The suture apparatus disclosed in U.S. Pat. No. 5,792,153 (PCT National Publication No. 10-500318) and Jpn. Pat. Appln. KOKOKU Publication No. 6-44,913 is mounted on the far-side end of the endoscope. This suture apparatus has a cavity having an opening in the flank. The cavity connects a biopsy channel and a suction channel. The cavity is subjected to vacuum suction through the suction channel. A part of an organic tissue is thereby drawn, in the shape of a U, into the cavity. A needle and a thread carrier in the biopsy channel are stabbed into the U-shaped part to suture the channel.
As described in Jpn. Pat. Appln. KOKAI Publication No. 11-313,826, a cap is provided on the tip of the endoscope, and a cavity having an opening is provided in the flank of the cap. In the tip, a suture tool is held by a holding forceps that is provided on the distal end portion of a sheath.
The organic tissue is sucked into the cavity through the opening made in the flank of the cap. The suture tool is stabbed into the organism tissue by using the holding forceps.
Any apparatus described in U.S. Pat. No. 5,792,153 (PCT National Publication No. 10-500318), Jpn. Pat. Appln. KOKOKU Publication No. 6-44,913, and Jpn. Pat. Appln. KOKAI Publication No. 11-313,826 is designed so that the organism tissue is sucked into the cavity having the opening in the flank of the tip portion of the endoscope.
Therefore, the cavity must be positioned, with the opening opposing a target region of the organism tissue, and then be depressurized. Thus, the opening of the cavity can hardly be moved to the target region. Consequently, the organism tissue cannot be fully drawn into the cavity when the cavity is depressurized only.
Further, a part of the stomach must be sucked in suturing the organism tissue to form an artificial valve for use in treatment of, for example, a gastro-esophageal reflux disease. However, the stomach wall is thicker than the tissues of the gullet and the like and is composed of a lumen-side mucous membrane, intermediate proper muscularis, and coat-side serous membrane. High fluidity is present, in particular between the mucous membrane and the proper muscular. To form a boss of a size suitable as a valve, it is essential to shorten and swell the tissue after capturing the proper muscularis. The conventional apparatuses can indeed capture the mucous membrane. However, it cannot easily capture the proper muscularis that underlies the mucous membrane. It is quite probable that the valve thus formed cannot be large and thick enough to prevent a backward flow reliably. To suture a damaged part securely, for example, it is necessary to suture the tissue including the proper muscularis or serous membrane. With the conventional apparatuses, however, it is difficult to capture the proper muscularis or serous membrane.
The object of the present invention is to provide an endoscopic suture apparatus capable of easily approaching a target region of an organic tissue and capturing the organism tissue in a holding portion to suture it.
According to an aspect of this invention, there is provided a endoscopic suture apparatus which comprises: an endoscope; a puncture member which has at least one sharp tip; a holding member which holds the puncture member and which is removably attached to an distal end of the endoscope; a clamping member which is configured to move back and forth with respect to the endoscope and to clamp living tissues; and a drive member which is configured to move the puncture member. The holding member has an opening portion which opens to an distal end. The opening portion, the distal end of the endoscope and the holding member define a treatment space. The clamping member is configured to project and retreat from and into the opening portion through the treatment space. The puncture member is configured to move in the treatment space, in a direction that intersects with a longitudinal direction of the endoscope.